A modern development of optics is optronics (also termed optoelectronics). Areas of applications of optronics are e.g. optical fiber communications, gauges for measurements of dimensions and for indications of positions, sensors for special analysis and for analysis of scattering etc. The optical equipment is comprised by optical, mechanical and electronic building elements.
It is desirable in optronic equipment to integrate the building elements into a stable and miniaturized unit. Especially in a development phase it is also preferred to have some of the elements easily replaceable. A requirement set for many of the elements is also that they should be adjustable as regards position and attitude, so that the optical beam path strived for in the equipment can be attained. The beam cross section, in e.g. semiconductor lasers and single mode fibres that are used in optical communications, have a diameter of the order of magnitude of micrometers. It is therefore in aligning such equipment necessary to be able to make adjustments with an accuracy and precision corresponding to a micrometer or submicrometer change in position. It is also important that components, which have been positioned, keep their position and attitude for a very long period of time, also in a mechanically adverse surrounding environment. It is common in a development phase that the optronical components are mounted on mechanical units obtained from a standardized building set of optical benches, sleds, holders, translational and rotational devices etc. It is unavoidable that such construction becomes bulky unstable and sensitive to vibrations. This is true even if the individual elements themselves are capable of e.g. a translation with a sufficient precision. Several designs of spring blocks of the type referred to are known, e.g. through an article in Journal of Scientific Instruments, Vol. 33, January 1956 titled "Some parasitic deflexions in parallell spring movements". This type of device has, however, only found a limited use.
The U.S. Pat. No. 4,930,858 refers to a positioning apparatus for optical fibres, which is intended to make two fibre ends, or one fibre end and a laser beam, parallel in relation to each other. The apparatus consists of 3 circular plates, provided at a distance from each other and connected to each other by "shoulders" integrated in the plates, that is by segment formed portions of material. In the plates central apertures are provided for mounting of e.g. a fibre end in the movable upper plate and to permit free optical beam path to e.g. a laser, which is mounted in the fixed part of the apparatus.
By means of screws, which apply forces on the plates crosswise these, that is in the axis direction of the apparatus, the upper movable plate can be forced to form a first angle with the central plate, and this, in the same way with further screws, which act in the axis direction, can be forced to form a second angle with the bottom plate. In these turning movements, which occur about the chords of the segments, both the movable plates will be tilted and therewith the part--e.g. the fibre end--which is to be adjusted.
This apparatus known can be used when two directions shall be brought to correspond and where it is of no importance if the movable component, which is to be adjusted, in addition to the desired turning also performs an inevitable, that is coupled, translation in the axis direction. This apparatus known thus cannot be used for positioning of an optical component, where it is required that the movable component during the adjustment maintains its angular position relatively to the fixed component. In other words, one should be able to be translate the movable component to a desired position without it being turned. Further it shall be possible in certain applications that the movable component be given a desired turn, which is accomplished by giving the point/points of action for the forces generated by the adjustment mechanism a certain location along the main axis of the system, that is the Z-axis.
The object of the invention and its most important characteristics.
The object of the invention is to produce a positioning device that allows for translations in serveral directions, a combination of translation and rotation or solely a rotation. Further all adjustments shall be made free of lash and the dimensions of the components,that are used, shall be sufficiently small, to allow for a compact integration with electronic or optoelectronic instruments. These objects have been solved thereby, that a holder that is attached to the system, on which the components to be positioned are fixed, that each elastic block is essentially rigid along a main axis (z) of the elastically undeformed cantilevered system, and is elastic in directions perpendicular to the axis, that the device has mechanisms for adjustment which apply adjustable forces between the basic element, or between some other to the latter fixedly joined element, and the cantilevered system or an arm fixed to this system, which latter may be the holder, acting in chosen directions, which translate or turn the component holder, when the elastic elements are elastically deformed.